Time Duration Converter
Enter a duration and its unit to see the equivalent in seconds, minutes, hours, days, weeks, and years.
A year here is the average calendar year (365.25 days), which accounts for leap years — useful for duration math, not for converting a specific calendar date.
How time duration conversion works
These units scale by fixed factors: 60 seconds per minute, 60 minutes per hour, 24 hours per day, and 7 days per week. A year is less exact, since calendar years vary between 365 and 366 days — this calculator uses the average of 365.25 days (31,557,600 seconds) to account for leap years.
Because a year isn't a fixed number of days, this calculator is best for duration math (like "how many hours is 3.5 years") rather than for finding an exact calendar date — use a date calculator for that instead.
Frequently asked questions
How many seconds are in a day?
86,400 seconds (24 hours × 60 minutes × 60 seconds).
Why is a year 365.25 days instead of 365?
The extra 0.25 days per year accounts for leap years — a leap year occurs roughly every 4 years to keep the calendar aligned with Earth's orbit, so the average year length across 4 years is 365.25 days.
How many weeks are in a year?
Approximately 52.18 weeks, using the average year length of 365.25 days divided by 7.